Head-mounted display device



FIG. 1 is a perspective view of a head-mounted display device;

FIG. 2 is a left side of the head-mounted display device, the right side view being a mirror image thereof;

FIG. 3 is a bottom view of the head-mounting display device;

FIG. 4 is a front view of the head-mounted display device;

FIG. 5 is a rear view of the head-mounted display device; and,

FIG. 6 is a top view of the head-mounted display device. 

The ornamental design for a head-mounted display device, as shown and described. 